Diplexed coupler for carrier aggregation

ABSTRACT

A wireless device is disclosed that can support carrier aggregation uplink (“CAUL”) communication using a single wideband coupler. A single wideband coupler that can operate or support some or all of the communication bands of the wireless device can be used in conjunction with one or more diplexers and/or filters to measure the power of individual communication bands involved in the transmission process. Further, the use of a wideband coupler and switching network to measure the transmit power from the one or more transmit paths or main paths of a wireless device can reduce the size of a transceiver and reduce the insertion loss attributed to the power measurement components compared to systems that use separate measurement systems for each transmit path. The power measurement system may occur in a separate path in electrical connection with the wideband coupler, which may therefore be termed a coupler path.

RELATED APPLICATION

This disclosure claims priority to U.S. Provisional Application No.62/234,813, which was filed on Sep. 30, 2015 and is titled “DIPLEXEDCOUPLER FOR CARRIER AGGREGATION,” the disclosure of which is expresslyincorporated by reference herein in its entirety for all purposes.

BACKGROUND Technical Field

This disclosure relates to carrier aggregation and, in particular, toprocessing received multiband signals.

Description of Related Technology

Often, wireless communication involves sending and receiving signalsalong a particular communication band. However, in some cases, wirelesscommunication may involve the use of multiple communication bands, whichis sometimes referred to as multiband communication and may involvemultiband signal processing. Usually, when a wireless device receives amultiband signal, the wireless device will perform carrier aggregationto aggregate the constituent signals. This can result in a widerbandwidth and it can be possible to receive data or communicationsignals at a higher data rate.

BRIEF DESCRIPTION OF THE DRAWINGS

Throughout the drawings, reference numbers are re-used to indicatecorrespondence between referenced elements. The drawings are provided toillustrate embodiments of the inventive subject matter described hereinand not to limit the scope thereof.

FIG. 1 illustrates a block diagram of an embodiment of a wireless devicethat includes a transceiver.

FIG. 2 illustrates a block diagram of an embodiment of the transceiverof FIG. 1.

FIG. 3A illustrates one embodiment of a transmitter signal pathincluding a power measurement module.

FIG. 3B illustrates another embodiment of a transmitter signal pathincluding the power measurement module.

FIG. 4A illustrates a circuit diagram for an embodiment of a firsttransceiver.

FIG. 4B illustrates a circuit diagram for an embodiment of a secondtransceiver.

FIG. 5 presents a flowchart of an embodiment of a coupler pathconfiguration process.

FIG. 6 illustrates a block diagram of an embodiment of a wirelessdevice.

SUMMARY

The systems, methods and devices of this disclosure each have severalinnovative aspects, no single one of which is solely responsible for theall of the desirable attributes disclosed herein. Details of one or moreimplementations of the subject matter described in this specificationare set forth in the accompanying drawings and the description below.

Certain aspects of the present disclosure relate to an antenna switchmodule. The antenna switch module may include a transmit switch incommunication with a plurality of transmit paths. At least one of thetransmit paths may support carrier aggregation transmission of a firstradio frequency band and a second radio frequency band. Further, theantenna switch module may include a coupler including at least a firstport and a second port. The first port may be in communication with thetransmit switch and the second port may be in communication with anantenna. The coupler may be configured to provide a transmit signal fromthe transmit switch to the antenna. Moreover, the antenna switch modulemay include a power measurement module in communication with thecoupler. The power measurement module may be part of a coupled path thatis separate from the plurality of transmit paths.

In certain embodiments, the power measurement module does not contributeto an insertion loss within the plurality of transmit paths. Someimplementations of the power measurement module include a first switchand a second switch. The first switch may be configured to switchbetween connecting a third port of the coupler to a third switch and afourth port of the coupler to the third switch. Further, the secondswitch may be configured to switch between connecting the third port ofthe coupler to a termination resistor and the fourth port of the couplerto the termination resistor. In some implementations, the third port ofthe coupler is connected to the third switch when the fourth port of thecoupler is connected to the termination resistor, and the third port ofthe coupler is connected to the termination resistor when the fourthport of the coupler is connected to the third switch.

Some implementations of the power measurement module further include thethird switch and a diplexer in communication with the third switch. Thethird switch may be configured to switch between connecting one of thethird port of the coupler or the fourth port of the coupler to one ofthe diplexer or a common coupler output. In some cases, the commoncoupler output corresponds to a power measurement for a third RF band.This third RF band may be a band that is not used for carrieraggregation transmission. Further, the diplexer may be configured tomultiplex a first signal corresponding to the first RF band and a secondsignal corresponding to the second RF band. Moreover, the diplexer maybe configured to output a first power measurement corresponding to thefirst RF band and a second power measurement corresponding to the secondRF band.

In some designs, the power measurement module further includes a lowpass filter, a high pass filter, and the third switch. The third switchmay be a single pole three throw switch. The first throw may beconfigured to connect the first switch to the low pass filter. Thesecond throw may be configured to connect the first switch to the highpass filter. The third throw may be configured to connect the firstswitch to a common coupler output without a filter. Further, the powermeasurement module may include the coupler.

Certain aspects of the present disclosure relate to a transceiver. Thetransceiver may include a power amplifier module that includes aplurality of power amplifiers. Each power amplifier from the pluralityof power amplifiers may correspond to a different radio frequency band.Further, the transceiver may include an antenna switch module incommunication with the power amplifier module. The antenna switch modulemay include a band selection switch, a coupler, and a power measurementmodule. The band selection switch may be in communication with aplurality of band paths. At least one of the band paths may supportcarrier aggregation transmission of a first RF band and a second RFband. The coupler may include a first port and a second port. The firstport may be in communication with the band selection switch and thesecond port may be in communication with an antenna. Further, thecoupler may be configured to provide a transmit signal from the bandselection switch to the antenna. Moreover, the power measurement modulemay be in communication with the coupler. In some cases, the powermeasurement module may be part of a coupled path that is separate fromthe plurality of band paths.

In certain embodiments, the power measurement module includes aplurality of switches configured to regulate the providing of a powermeasurement from the coupler to at least one of the plurality of poweramplifiers. Further, the power measurement may correspond to one of anoutput power at the antenna or a reflected power from the antenna. Insome implementations, the power measurement module further includes afirst diplexer in communication with one of the plurality of switches.The first diplexer may be configured to multiplex a first signalcorresponding to the first RF band and a second signal corresponding tothe second RF band.

Moreover, the transceiver may further comprise a second diplexer. Thesecond diplexer may be in communication with a first power amplifier anda second power amplifier from the plurality of power amplifiers. Thefirst power amplifier may correspond to the first RF band and the secondpower amplifier may correspond to the second RF band. Further, thesecond diplexer may be configured to multiplex a third signalcorresponding to the first RF band and a fourth signal corresponding tothe second RF band. In some cases, the first signal and the third signalare the same frequency and the first signal has a different power levelthan the third signal. Moreover, in some cases, the second signal andthe fourth signal are the same frequency and the second signal has adifferent power level than the fourth signal. Further, in some cases,the second diplexer generates a 1-2 dB insertion loss and the firstdiplexer generates a 2-5 dB insertion loss. In certain embodiments, thepower amplifier module is configured to modify the input power to atleast one power amplifier from the plurality of power amplifiers basedat least in part on a power measurement signal from the powermeasurement module.

Certain aspects of the present disclosure relate to a wireless device.The wireless device may include an antenna configured to receive andtransmit a wireless signal. The antenna may be capable of transmitting acarrier aggregation signal. The wireless device may further include atransceiver in communication with the antenna. The transceiver mayinclude a power amplifier module and an antenna switch module incommunication with the antenna and the power amplifier module. Further,the antenna switch module may include a band selection switch, acoupler, and a power measurement module. The band selection switch maybe in communication with a plurality of band paths. At least one of theband paths may support transmission of a carrier aggregation signalincluding at least a first signal of a first RF band and a second signalof a second RF band. The coupler may be configured to provide a transmitsignal from the band selection switch to the antenna. Further, the powermeasurement module may be part of a coupled path that is separate fromthe plurality of band paths.

DETAILED DESCRIPTION Introduction

Some wireless devices support communication over multiple radiofrequency (RF) bands. In some cases, a wireless device may communicateover multiple frequency or RF bands at the same time. Communicating overmultiple frequency bands may include a wireless device transmitting dataand/or voice (e.g., audio data) synchronously over multiplecommunication bands. This synchronous or simultaneous transmission overmultiple RF bands may be referred to as uplink carrier aggregation orcarrier aggregation uplink (“CAUL”). Using CAUL may enable transmissionat higher data rates because, for example, each carrier may transmitsome of the data. Thus, for example, in some cases, instead of a singlecarrier transmitting data at rate X, two carriers can transmit datatogether at a rate of up to 2X. Devices that are capable of CAULtypically include at least two power amplifiers transmitting signals atthe same time. The signals may be combined and transmitted together overa single communication connection using, for example, time divisionduplex (TDD) communication, which can communicate both carriers togetherover a single uplink connection.

There is often a need to monitor the power output by the poweramplifiers involved in the transmission process or within thetransmission lines or paths between the power amplifier(s) and theantenna(s) in the wireless device. For example, it may be desirable tosense the output power of the wireless device so that the input power toone or more of the power amplifiers can be adjusted so as to maintain aconstant or relatively constant (e.g., within a threshold powervariation) at the antenna(s). The power output at an antenna may varydue to a number of factors, such as distance from a base station,positioning of a user's hand, or the physical environment around thewireless device (e.g., placed on a metal table or a wooden table, etc.).As another example of, it may be desirable to sense the output power ofthe wireless device to determine whether the device is operating withina target specific absorption rate (SAR) range or below a SAR threshold.The SAR for a wireless device is usually related to a safety parameterfor the amount of radiation or RF energy permitted by a regulatoryagency or other government agency to be emitted with in a particulardistance range of a user.

One method of monitoring the power output of a power amplifier and/orthe power to be output by an antenna is to place a coupler on thetransmission line or output path between the power amplifier and theantenna. This coupler may be used to provide a portion of the transmitpower along the transmit path within the wireless device to a feedbacksystem that can be used to determine the amount of the transmit powerbeing provided to the antenna for output. For wireless devices withsingle band transmission or for wireless devices with multiple bandtransmission that transmit from a single band at a time (e.g., with asingle active transmitter), this coupler can be used to measure thetransmit output power for each transmit band.

However, a wireless device that supports CAUL will generally combine theoutput of multiple power amplifiers along a single transmit path withinthe wireless device for transmission in a single communicationconnection. Thus, in such cases, the wireless device may includemultiple couplers. A coupler may be placed subsequent to each poweramplifier that corresponds to a communication band used in CAUL by thewireless device. These couplers are generally positioned before thetransmit path for each of the CAUL supporting power amplifiers arecombined into a single transmit path. Furthermore, each of the couplersmay be designed to support a particular communication band associatedwith the power amplifier. Thus, each coupler may be designed andconfigured uniquely, thereby reducing the ability to swap or sharecoupler designs among the transmit paths in the manufacturing processand increasing the resources required to design and manufacture thewireless device. Further, adding couplers to the transmit path mayincrease the size of the transmitter die or module and typically alsoadds insertion loss to the transmit path. As a result, the strength ofthe transmit signal may be reduced or more power may be required by thetransmitter to maintain output signal strength resulting in an increasedbattery drain. Some wireless devices can support 10, 12, or moretransmit bands and thus, the number of couplers may be 10, 12 or morecompounding the problems described above.

Certain embodiments described herein enable a wireless device to supportCAUL while using a single wideband coupler. Often, the communicationbands supported by a wireless device are separated by 100 MHz or more.In some cases, less separation may exist between some of thecommunication bands of a wireless device, but the communication bandsused for CAUL are separated by at least 100 MHz. Thus, a single widebandcoupler that can operate or support some or all of the communicationbands of the wireless device can be used in conjunction with one or morediplexers and/or filters to measure the power of individualcommunication bands involved in the transmission process. Further,certain embodiments described herein can remove components used in themeasurement of the transmit power from the one or more transmit paths ormain paths of a wireless device reducing the insertion loss attributedto the power measurement components. Instead, the power measurement mayoccur in a separate path in electrical connection with the widebandcoupler, which may therefore be termed a coupler path.

First Example Wireless Device

FIG. 1 illustrates a block diagram of an embodiment of a wireless device100 that includes a transceiver 102. The transceiver 102 may include afeedback loop 106 that enables the transceiver 102 to measure ordetermine power provided to the antenna 104 for output. Using thismeasured power value, the transceiver 102 can adjust power input topower amplifiers of the transceiver 102. Embodiments of the transceiver102 are described in more detail below with respect to FIG. 2.

Although the feedback loop 106 is illustrated as providing an output ofthe transceiver 102 back to the transceiver 102 is an input, in somecases the feedback loop 106 may be internal to the transceiver 102. Inother words, components or devices within the transceiver 102 mayfeedback information to other components within the transceiver 102 tomeasure a power value and/or to act on a measurement of the power value.Further, it should be understood that the transceiver 102 may be atransmitter. In some such cases, the wireless device 100 may include aseparate receiver.

Example Transceiver

FIG. 2 illustrates a block diagram of an embodiment of the transceiver102 of FIG. 1. The transceiver 102 includes a power amplifier module202, a diplexer 204, a duplexer 206 or a duplex filter bank 206, and anantenna switch module 208. In some cases, the duplex filter bank 206 mayinclude a bank or set of filters that support multiple frequency bands.The power amplifier module 202 generally includes a plurality of poweramplifiers. Further the power amplifier module 202 may include acontroller that controls the operation of the power amplifiers. Thiscontroller may activate or deactivate one or more of the poweramplifiers. Further, the power amplifier module 202 and/or itscontroller may include bias circuitry for biasing the plurality of poweramplifiers and power control circuitry for controlling the input powerprovided to a plurality of power amplifiers.

As illustrated in FIG. 2, the power amplifier module 202 may include anumber of output paths. Each of these output paths may be associatedwith a different power amplifier of the power amplifier module 202.Further, each of the output paths may be associated with a differentcommunication band or transmit band. For example, as illustrated in FIG.2, the power amplifier module 202 has six outputs corresponding, inorder from top to bottom, to band A, band B, band C, band D, band E, andband F.

The transceiver 102 in this particular example may be capable of CAULcommunication with respect to bands E and F. Thus, the transmit pathsfor band E and band F that that extend from the power amplifier module202 may be combined into a single transmit path by, for example, thediplexer 204. The diplexer 204 may implement frequency domainmultiplexing to combine the band E signal in the band F signal into asingle transmit signal. Typically, band E and band F are made up ofdisjoint frequencies enabling the two signals to be combined withoutinterfering with each other. Thus, both the band E signal and the band Fsignal can share the same communication channel.

Although only two communication bands are illustrated as being combined,in some embodiments more than two communication bands may be combined bya diplexer into a single communication channel. Further, although onlyone CAUL communication channel is illustrated, the transceiver 102 mayinclude multiple CAUL channels. In other words, in some cases, multiplesets of communication bands may be combined to perform carrieraggregation transmission.

The duplex filter bank 206 enables one or more of the communicationbands to be used for both transmitting a signal and receiving a signal.The duplex filter bank 206 can direct a signal received from the antennaswitch module 208 to a receiver (not shown) included in the transceiver102. In some cases, the duplex filter bank 206 may be omitted. Forexample, the transceiver 102 may instead be a transmitter that isseparate from a receiver. In some such cases, the duplex filter bank 206may be unnecessary. Although there is no duplexer, or duplex filterbank, illustrated with respect to the aggregated communication bands Eand F, in some cases the communication channel associated with bands Eand F may also include a duplexer enabling the transceiver 102 toreceive band E and/or F signals.

In some embodiments, a signal may be transmitted on one of band E orband F while no signal is transmitted on the other band. Further,typically only one transmit path corresponding to one communicationband, or one aggregated transmit path corresponding to one set ofaggregated communication bands, transmits a signal or is active at atime. The antenna switch module 208 may control which transmit path isprovided to the antenna 104.

The antenna switch module 208 may be controlled by a baseband processor210. The baseband processor 210 may provide a control signal to theantenna switch module 208 to select a transmit path to transmit asignal. Further, the selection of the transmit path may be based on aselection of a communication band identified by a base station forreceiving signals from the wireless device 100.

The baseband processor 210 includes a call processor 214 and a model212. The modem can perform modulation and demodulation of data and voicefor transmission. The call processor 214 may control the timing ofcommunication with the base station. Further, the call processor 214 maycontrol the switches of the antenna switch module 208. In someembodiments, the call processor 214 may also control the poweramplifiers of the power amplifier module 202.

Example Transceiver Signal Paths

FIG. 3A illustrates one embodiment of a transmitter signal path 300including a power measurement module 304. As previously described, thereare a number of reasons why it is beneficial to monitor the output ortransmit power for transmission of the signal. Thus, some wirelessdevices may include a power measurement module 302 within thetransmission or transceiver signal path 300.

In some implementations of a device's transmission path, the poweramplifier module 202 may provide a transmission signal at a particularpower level to the power measurement module 302. The power measurementmodule 302 may feedback a signal to circuitry that provides the transmitsignal to the power amplifier module 202 along feedback path 304. Basedon the feedback signal received along the feedback path 304, thecircuitry providing power input to the power amplifier module 202 mayadjust input power provided to one or more power amplifiers of the poweramplifier module 202.

Further, the power measurement module 302 may forward the signalreceived from the power amplifier module 202 to the antenna switchmodule 208. In some cases, the antenna switch module 208 may filter orfrom among a plurality of signals received from the power measurementmodule 302. The transmit signal may be provided to the antenna 104 fortransmission to a base station or another device.

The power measurement module 302 may add to the insertion loss thatoccurs along the transmission path 300. Thus, in some cases, the poweramplifier module 202 may operate at or use more power to compensate forthe insertion loss of the power measurement module 302. Further, thepower efficiency of the wireless device that includes the transmissionsignal path 300 may be reduced due to the power measurement module 302.

FIG. 3B illustrates another embodiment of a transmitter signal pathincluding the power measurement module 302. In the embodimentillustrated in FIG. 3B, the power measurement module 302 is removed fromthe transmitter or main signal path 310 and is instead placed within acoupled path 312. Advantageously, in certain embodiments, by removingthe power measurement module 302 from the main signal path 310 insertionloss along the main signal path 310 is reduced compared to the transmitpath 300 of FIG. 3A. Further, by reducing the insertion loss along themain signal path 310 power efficiency is improved for the poweramplifier module 202 of FIG. 3B compared to that of FIG. 3A.

Although the power measurement module 302 is illustrated as a separatemodule, in some cases the power measurement module 302 may be part ofthe antenna switch module 208. However, although the power measurementmodule 302 may be part of the antenna switch module 208, the powermeasurement module 302 may still be separate from the main transmit path310.

Example Circuit Diagrams for a Transceiver

FIG. 4A illustrates a portion of a circuit diagram of a comparisontransceiver 401 that, in some embodiments, can be used in place of thetransceiver 102 previously described with respect to FIG. 1 anddescribed in more detail below with respect to FIG. 4B. The transceiver401 includes a power amplifier 402 corresponding to band E and a poweramplifier 404 corresponding to band F. To simplify the drawing, thepower amplifiers associated with the bands A-D have been omitted. In theillustrated example, bands A-D are not involved in CAUL. Thus,typically, only one of the transmit paths corresponding to bands A-Dwill be active at a time. On the other hand, the transmit paths forbands E and F are capable of CAUL and may both be active at the sametime. Signals associated with bands E and F, which are capable of CAUL,may be combined by a diplexer 204 before being provided to a switch 406.

As illustrated, the switch 406 may be a single pole five throw switch(SP5T). In other words, the switch may include a throw for each transmitpath. The position of the switch may be selected based on thecommunication band or bands that are selected for communication.

The transceiver 401 may further include a coupler 462 that is pairedwith two switches 414 and 416. The combination of the coupler 462 andthe switches 414 and 416 may serve to measure power along the transmitpath and to adjust a power amplifier based on the measured power in thetransmit path. The power amplifier that is adjusted may be the poweramplifier that corresponds to the particular communication band. Thus,for example, if band A is the selected communication band, the measuredpower along the transmit path may be used to adjust the power suppliedto the power amplifier (not shown) associated with the band Acommunication path.

If the signal being transmitted is a carrier aggregated signal, such asa combined band E and band F signal, the measured power that is measuredby the coupler 462 will represent the power of the combined signal.Thus, in some cases, it may be difficult or not possible to determinewhether to adjust or how much to adjust the power supplied to the poweramplifier 402 associated with band E and the power amplifier 404associated with band F.

One solution to the above problem is to measure the power of theindividual communication bands before they are combined by the diplexer204. For example, the power of the portion of the carrier aggregatedsignal associated with band E may be measured by the coupler 450, withthe switches 458 and 460 being configured based on whether the forwardor reverse power is being measured. Similarly, the power of the portionof the carrier aggregated signal associated with band F may be measuredby the coupler 452, with the switches 454 and 456 being configured basedon whether the forward or reverse power is being measured.

As illustrated in FIG. 4A, each of the transmit paths corresponding tobands that may be used in carrier aggregated communication (e.g., band Eand band F) are associated with a coupler and a pair of switches tofacilitate the power measurement of the bands. Although only two bandsare illustrated as being eligible for carrier aggregated communication,in some implementations, more than two bands may be eligible for carrieraggregation. For example, in some embodiments, bands C and D may also beeligible for carrier aggregation. Further, there may be any number ofcombinations of eligible bands that may be used for carrier aggregation.For example, bands D, E, and F may be aggregated in some cases. In othercases, bands C and D may be aggregated, bands D and E may be aggregated,or bands E and F may be aggregated. For wireless devices to support eachof these possible carrier aggregations using the solution described inthe previous paragraph, each of the transmit lines may include a couplerand a pair of switches as described with respect to the bands E and F ofFIG. 4A. Thus, the more bands that are eligible for carrier aggregation,the more couplers and switches that are included in the transceiver 401.The addition of couplers and switches can result in more cost and alarger transceiver. Further, additional power may be required for theadditional switches. Moreover, the additional couplers and switcheswithin the communication paths can add insertion loss in the transmitpath causing a reduction in the strength of the transmit signal orrequiring greater power to compensate for the insertion loss.

FIG. 4B illustrates a portion of a circuit diagram for an embodiment ofa second transceiver 102. In some embodiments, the transceiver 102reduces the size of the transceiver compared to the transceiver 401, andalso reduces insertion loss and the required power of the transceiver401.

The transceiver 102 includes a power amplifier 402 corresponding to bandE and a power amplifier 404 corresponding to band F. To simplify thedrawing, the power amplifiers associated with the bands A-D have beenomitted. However, it should be understood that each band receives asignal from a power amplifier that may be included as part of the poweramplifier module 202 previously discussed. In some cases, some of thebands may share a power amplifier. For example, bands A and B may sharea power amplifier. In such cases, a switch may be used to determine thetransmit path that is electrically connected to the power amplifier.Alternatively, a single transmit path may be configured to transmitsignals of either band A or band B. In some such cases, it may beunnecessary to have multiple transmit paths because only one of band Aor band B may communicate at a time if carrier aggregation is notsupported for bands A and B.

Each transmit path associated with one of the bands may be in electricalcommunication with the antenna switch module 208. In the illustratedexample, bands A-D are not involved in CAUL. Thus, typically, only oneof the transmit paths corresponding to bands A-D will be active at atime. On the other hand, the transmit paths for bands E and F arecapable of CAUL and may both be active at the same time. Further, aspreviously discussed, signals associated with bands E and F that arecapable of CAUL may be combined by a diplexer 204 before being providedto the antenna switch module 208.

Although FIG. 4B illustrates two signal bands, band E and band F, beingcombined for CAUL communication via the diplexer 204, it should beunderstood that more than two communication bands can be used in CAULcommunication. For example, the diplexer 204 may combine three, four, ormore communication bands into an aggregated carrier signal. In someembodiments, multiple diplexers may be chained together to create acarrier aggregated signal from multiple frequency bands.

Further, although the transceiver 102 of FIG. 4B only includes one pairof CAUL capable frequency bands, it should be understood that atransceiver may include multiple sets of CAUL capable frequency bands.In other words, multiple pairs of frequency bands may be combined by adiplexer. In some cases, a pair of communication bands may be combinedfor CAUL communication and a separate set of three communication bandsmay be combined with a triplexer for CAUL communication. Further, insome cases, a frequency band may be paired with multiple groups offrequency bands for CAUL communication. In such a case, a switch may beused to select the aggregation group that is to include a sharedfrequency band at a particular point in time. This determination may bebased on the RF bands supported by a base station as identified by thebase station.

Although more than two frequency bands can be aggregated, increasing thenumber of aggregated carrier bands can increase the current drain on thewireless device and increase the amount of heat generated. Thus, incertain embodiments, the amount of frequency bands aggregated may bebalanced against electrical and physical constraints for a particularwireless device. Moreover, in some cases, the physical location of theaggregated transmit path within the wireless device may be separatedfrom heat sensitive components within the wireless device to counter theincreased heat generation from the carrier aggregated transmit path.

Antenna switch module 208 includes a switch 406. As illustrated, theswitch 406 may be a single pole five throw switch (SP5T). In otherwords, the switch may include a throw for each transmit path. Thus, fortransceivers that support a different number of communication bands andthus include a different number of transmit paths, the switch 406 mayhave a different number of throws. Alternatively, in certainembodiments, the switch 406 may be made up of a plurality of switches.At least some of the plurality of switches may be single pole two throwswitches (SP2T) or single pole one throw switches (SP1T). In some suchembodiments, the controller 412 may select the switch to electricallyconnect a transmit path to the antenna were may select the switch toclose while connecting the other switches to ground or keeping the otherswitches open.

In the illustrated embodiment with the SP5T, the controller 412 mayselect the transmit path to electrically connect to the antenna based ona signal received from, for example, the baseband processor 210.Further, the baseband processor 210 may provide a control signal to thecontroller 412 based on a command received from a base station or otherdevice communicating with the wireless device 100.

The antenna switch module 208 may further include a power measurementmodule 410. The power measurement module 410 may include a coupler 408that is configured to sample or otherwise couple a portion of the powerof the transmit signal being provided along the main transmit path tothe coupled path that includes the remaining components of the powermeasurement module 410. Typically, the coupler 408 will be a widebandcoupler, thereby enabling the coupler to sample or otherwise couple aportion of the power of a a number of supported transmit frequencybands. Generally, the coupler 408 will support a greater number offrequency bands than the coupler 462, which may be considered anarrowband coupler, or a coupler that supports fewer frequency bandsthan the coupler 408. For example, the coupler 408 may be able toprocess frequencies from bands A, B, C, D, E, and F, while the coupler462 may not support bands E and F. Advantageously, in certainembodiments, by using the wideband coupler 408, the couplers 450 and 452can be eliminated. Eliminating the couplers 450 and 452 can reduce thesize of the transceiver 102 and reduce required transmit power. Theinput port of the coupler 408 may receive a signal from the transmitpath selected by the controller 412 and electrically connected to theantenna via the switch 406. The output port of the coupler 408 providesthe received signal from the transmit path to the antenna fortransmission.

The power measurement module 410 may further include a pair of switches414 and 416 that facilitate measuring the power of the transmit signaland which may be controlled by the controller 412. The switch 414 mayselect a third port of the coupler 408 to be the coupled port. Byadjusting which port from the coupler is the coupled port, the powermeasurement module 410 can measure one of the forward power beingprovided to the antenna, or the reflected or reverse power. When theswitch 414 is configured such that the pole is to the left in FIG. 4B,the left port of the coupler 408 is electrically connected to the switch414 and the power measurement module 410 can measure the forward powerof the coupler 408. Conversely, when the switch 414 is configured sothat the pole is to the right in FIG. 4B, the right port of the coupler408 is electrically connected to the switch 414 and the powermeasurement module 410 can measure the reflected power of the coupler408.

In certain embodiments, the controller 412 may continuously orintermittently adjust the switch 414 to enable the power measurementmodule 410 to measure the forward power and the reflected power of thecoupler 408 continuously or intermittently. For instance, the controller412 may adjust the switch every 1 ms, every 5 ms, every 5 clock cycles,etc.

The switch 416 may select a port of the coupler 408 to be the isolatedor terminated port. When the forward power of the coupler 408 is beingmeasured, the switch 416 terminates the port on the right of the coupler408. Conversely, when the reflected power of the coupler 408 is beingmeasured, the switch terminates the port on the left of the coupler 408.The switch 416 may terminate a port of the coupler 408 by electricallyconnecting the coupler port to the termination or the terminationresistor 418. The switch 416 may adjust which switch is terminated basedon a signal from the controller 412.

The power measurement module 410 may further include a switch 420 thatadjusts the output destination of the measured power based on a controlsignal from the controller 412. The coupler 408 can manage each of thenon-carrier aggregated bands (e.g., bands A-D). Thus, if a signal beingtransmitted is using a communication band that is not used in carrieraggregation, such as one of bands A-D, the switch 420 may electricallyconnect the measured power from the coupler 408 directly to the outputpath 424. This output signal may then be directed back to thecorresponding PA or to circuitry providing input power for the PA orPAM.

On the other hand, if the signal being transmitted is using one or morecommunication bands capable of carrier aggregation, the switch 420 mayelectrically connect the measured power from the coupler 408 to thediplexer 422. This diplexer 422 can split the measured power into itsconstituent signal bands. Thus, the diplexer 422 can provide a signalthat is within frequency band F to the output path 426, which may inturn provide the measured band F power to the power amplifier 404, or acontroller that can modify the input power to or configuration of poweramplifier 404. Further, the diplexer 422 can provide a signal that iswithin frequency band E to the output path 428, which may in turnprovide the measured band E power to the power amplifier 402, or acontroller that can modify the input power to or configuration of poweramplifier 402.

Generally, the diplexer 422 is a type of filter or filter network, whichmay include a number of different filters (e.g., a combination oflow-pass and high-pass filters). This filter network can separate thecarrier aggregated bands into its constituent frequency bands. Forexample, a first filter may pass the band E frequency while blocking theband F frequency and a second filter may pass the band F frequency whileblocking the band E frequency. Further, in some such cases, the filternetwork may include a switch that can toggle between the high passfilter and the low pass filter.

In certain embodiments, the band F coupled output 426 provides thesignal to a band E frequency detector and the band E coupled outputprovides the signal to a band F frequency detector. The band E detectorcan detect and/or filter, using for example a bandpass filter, theportion of the carrier aggregated signal that is within the band Efrequency range and provide the band E portion of the signal to the bandE PA 402, or its corresponding controller. Similarly, the band Fdetector can detect and/or filter, using for example a bandpass filter,the portion of the carrier aggregated signal that is within the band Ffrequency range and provide the band F portion of the signal to the bandF PA 404, or its corresponding controller. The filter can successfullyseparate the signal into its constituent frequency bands because thefrequency bands used for carrier aggregation are typically separated infrequency by, for example, a 100 MHz, 200 MHz, etc. In some cases, thefrequency bands may be separated by much more than 100 MHz. In someembodiments, the diplexer 422 may be omitted without being replaced by afilter network or alternative system. In such cases, the PA input powerassociated with the PAs 402 and 404 may be adjusted based on thecomposite power for the carrier aggregated signal instead of the powerfor the individual communication bands involved in the CAULcommunication.

As previously described, bands E and F are capable of CAUL communicationin the transceiver 102 example of FIG. 4B. However, the transceiver 102may also receive signals in communication bands E and F. Further, insome cases, bands E and F may also transmit signals individually, or ina non-carrier aggregated form. This may occur, for example, when a basestation does not support CAUL for bands E and F. Thus, in some cases,the transceiver 102 may be capable of switching between CAUL, separatetransmission for bands E and/or F, and receiving signals along bands Eand/or F. In some cases, assuming TDD communication, the wireless device100 may have transmit bursts and receive bursts and each band could havea different duty cycle.

In one non-limiting example, the transceiver 102 could transmit fromboth bands E and F using CAUL communication for 30% of the time, thetransceiver 102 could transmit from frequency band E in a non-carrieraggregation transmit mode 20% while receiving a signal on band F, andcan transmit or receive signals on one of bands A-D for 50% of the time.A variety of communication configurations are possible for a TDD systemand the selection of bands used for transmitting and/or receiving asignal at a given point of time may be dependent on the base station orthe configuration of the wireless device. On the other hand, in somefrequency division duplex (FDD) systems, multiple frequency bands maytransmit and/or receive signals at the same time. Further, in someembodiments, the power measurement module 410 can measure forward poweron one communication path and then measure reverse power on anothercommunication path.

As previously discussed, in some alternative designs, the powermeasurement module is placed within the transmit path. In some suchcases, couplers are placed within each transmit path, or within eachtransmit path associated with an aggregated frequency band. Such adesign may result in greater insertion loss and increased size for thetransceiver 102. This insertion loss can increase current drain anddegrade the overall performance of the wireless device. Advantageously,by creating a coupled path that is separate from the main transmit pathsand by using a wideband coupler at the node between the main transmitpath and the coupled path, the number of couplers can be reducedresulting in a smaller and cheaper transceiver compared to designs thatinclude the power measurement within the main transmit path. Further,insertion loss may be reduced in the main transmit path compared todesigns that include the power measurement within the main transmitpath. Moreover, the number of switches used by the transceiver 102 maybe reduced compared to other designs, such as the transceiver 401,resulting in further space and power savings.

In certain embodiments, because the diplexer 204 is within the maintransmit path, it can be more important for the diplexer 204 to have alower insertion loss compared to the diplexer 422, which is in thecoupled path and not the main transmit path. Thus, for example, thediplexer 204 may be designed with an insertion loss of 1-2 dB maximumwhile the diplexer 422 may be designed to accommodate an insertion lossof up to 5 dB. Advantageously, by permitting a higher insertion loss inthe diplexer 422, the diplexer 422 may be smaller and cheaper comparedto the diplexer 204. Further, the diplexer 422 may be integrated on asingle die with other components of the power measurement module 410 orantenna switch module 208. On the other hand, in certain embodiments,the diplexer 204 due, for example, to its insertion loss constraints maybe a separate or discrete element and may, in some cases, be a lumpedelement. In some embodiments, the transceiver 102, or parts thereof, maybe part of a front-end module (FEM).

Example Coupler Path Configuration Process

FIG. 5 presents a flowchart of an embodiment of a coupler pathconfiguration process 500. The process 500 can be implemented by anysystem that can configure a coupler or coupled path to measure a forwardor reflected power along a transmit or main path. For example, theprocess 500 may be performed by a controller 412, a power measurementmodule 410, a baseband processor 210, or a call processor 214, to name afew. Although one or more systems may implement the process 500, inwhole or in part, to simplify discussion, the process 500 will bedescribed with respect to particular systems.

The process 500 begins at the block 502 where, for example, the basebandprocessor 210 receives a command from a base station to establish acommunication connection. In some cases, the wireless device thatincludes the baseband processor 210 may have already established acommunication connection with another base station, but may be goingthrough a handover process to switch to the base station because of achange in location by the user of the wireless device. In some cases,the block 502 is omitted because, for example, the wireless devicerequested to establish the communication connection.

At block 504, the call processor 214 receives an indication of a radiofrequency band to use for uplink communication. This indication may comefrom the base station. In some cases, the call processor 214 may receivean indication of multiple RF bands. For example, if the basebandprocessor in the wireless device supports carrier aggregation, callprocessor 214 may receive an indication of multiple RF bands that can beused with carrier aggregation.

At block 506, the call processor 214 identifies a transmission pathwithin the device associated with the RF band identified at the block504. In some cases, multiple transmission paths may be identified. Forexample, suppose that the RF bands identified are associated with CAULtransmission. Although the portion of the transmit path may be combined,as illustrated in FIG. 4B, at least some of the transmit paths (e.g.,the portion between the PAs 402, 404 and the diplexer 204) for the CAULbands may be separate. Thus, in such cases, multiple transmission paths,or portions thereof, may be identified when multiple RFG bands areidentified at the block 504.

The call processor 214, at block 508, configures switches within thecoupler path of the transceiver 102 to provide a power measurement for apower amplifier within the transmission path associated with the RF bandto the power amplifier module 202. In some cases, the call processor 214may configure the switches within the coupler path by providing a one ormore control signals to the controller 412 of the transceiver 102. Insome embodiments, the process 500 may further include receiving acontrol signal to determine whether to provide a measurement of forwardpower or reflected power to the power amplifier module. The block 508may also include adjusting or controlling the switch 406 to select thetransmit path corresponding to the communication band(s) requested by,for example, the base station.

In certain embodiments, at least parts of the process 500 may beperformed continuously or intermittently. For example, the base stationmay periodically send messages to the call processor 214 instructing thewireless device to adjust its power output. In such cases, theoperations associated with the block 508 may be repeated as the powerlevel in the power amplifier corresponding to the transmit band isadjusted. Further, the base station may request that the wireless devicechange its transmission band or switch to/from carrier aggregationtransmission. In such cases, the operations associated with the block506 may be repeated to determine the new transmission path associatedwith the requested RF band(s).

Second Example Wireless Device

FIG. 6 illustrates a block diagram of an embodiment of a wireless device600. The wireless device 600 is a more detailed version of the wirelessdevice 100 and may include some or all of the embodiments previouslydescribed with respect to the wireless device 100.

In the example illustrated in FIG. 6, the wireless device may include anumber of front-end module (FEMs) 640. In some cases, a different FEMmay be included for different communication standards or technologies(e.g., 2G, 3G, 4G LTE, 5G, etc.). Further, although illustratedseparately, in some cases, an FEM 640 may include the transceiver 102.

Other connections between the various components of the wireless device600 are possible, and are omitted from FIG. 6 for clarity ofillustration only and not to limit the disclosure. For example, thepower management component 606 may be electrically connected to thebaseband processor 210, the FEMs 640, the DSP 612, or other components614. As a second example, the baseband processor 210 may be connected toa user interface processor 616 that may facilitate input and output ofvoice and/or data provided to and received from the user. The basebandprocessor 210 can also be connected to a memory 618 that may beconfigured to store data and/or instructions to facilitate the operationof the wireless device 600, and/or to provide storage of information forthe user.

In addition to the aforementioned components, the wireless device mayinclude one or more central processors 620. Each central processor 620may include one or more processor cores. Further, the wireless device600 may include one or more antennas 622A, 622B. In some cases, one ormore of the antennas of the wireless device 600 may be configured totransmit and receive at different frequencies or within differentfrequency ranges. Further, one or more of the antennas may be configuredto work with different wireless networks. Thus, for example, the antenna622A may be configured to transmit and receive signals over a 2Gnetwork, and the antenna 622B may be configured to transmit and receivesignals over a 3G network. In some cases, the antennas 622A and 622B mayboth be configured to transmit and receive signals over, for example, a2.5G network, but at different frequencies. Moreover, one of theantennas 622A or 622B may be a diversity antenna, which may communicatewith a diversity module 624.

A number of other wireless device configurations can utilize one or morefeatures described herein. For example, a wireless device can includeadditional antennas such as diversity antenna, and additionalconnectivity features such as Wi-Fi, Bluetooth, and GPS. Further, thewireless device 600 may include any number of additional components,such as analog to digital converters, digital to analog converters,graphics processing units, solid state drives, etc. Moreover, thewireless device 600 can include any type of device that may communicateover one or more wireless networks using CAUL communication. Forexample, the wireless device 600 may be a cellular phone, including asmartphone or a dumbphone, a tablet, a laptop, a video game device, asmart appliance, etc.

Terminology

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” The term “coupled” is used to refer tothe connection between two elements, the term refers to two or moreelements that may be either directly connected, or connected by way ofone or more intermediate elements. Additionally, the words “herein,”“above,” “below,” and words of similar import, when used in thisapplication, shall refer to this application as a whole and not to anyparticular portions of this application. Where the context permits,words in the above Detailed Description using the singular or pluralnumber may also include the plural or singular number respectively. Theword “or” in reference to a list of two or more items, that word coversall of the following interpretations of the word: any of the items inthe list, all of the items in the list, and any combination of the itemsin the list.

The above detailed description of embodiments of the inventions are notintended to be exhaustive or to limit the inventions to the precise formdisclosed above. While specific embodiments of, and examples for, theinventions are described above for illustrative purposes, variousequivalent modifications are possible within the scope of theinventions, as those skilled in the relevant art will recognize. Forexample, while processes or blocks are presented in a given order,alternative embodiments may perform routines having steps, or employsystems having blocks, in a different order, and some processes orblocks may be deleted, moved, added, subdivided, combined, and/ormodified. Each of these processes or blocks may be implemented in avariety of different ways. Also, while processes or blocks are at timesshown as being performed in series, these processes or blocks mayinstead be performed in parallel, or may be performed at differenttimes.

The teachings of the inventions provided herein can be applied to othersystems, not necessarily the system described above. The elements andacts of the various embodiments described above can be combined toprovide further embodiments.

Conditional language used herein, such as, among others, “can,” “might,”“may,” “e.g.,” and the like, unless specifically stated otherwise, orotherwise understood within the context as used, is generally intendedto convey that certain embodiments include, while other embodiments donot include, certain features, elements and/or states. Thus, suchconditional language is not generally intended to imply that features,elements and/or states are in any way required for one or moreembodiments or that one or more embodiments necessarily include logicfor deciding, with or without author input or prompting, whether thesefeatures, elements and/or states are included or are to be performed inany particular embodiment.

While certain embodiments of the inventions have been described, theseembodiments have been presented by way of example only, and are notintended to limit the scope of the disclosure. Indeed, the novel methodsand systems described herein may be embodied in a variety of otherforms; furthermore, various omissions, substitutions and changes in theform of the methods and systems described herein may be made withoutdeparting from the spirit of the disclosure. The accompanying claims andtheir equivalents are intended to cover such forms or modifications aswould fall within the scope and spirit of the disclosure.

What is claimed is:
 1. An antenna switch module comprising: a transmitswitch in communication with a plurality of transmit paths, at least oneof the transmit paths supporting carrier aggregation transmission of afirst radio frequency band and a second radio frequency band; a couplerincluding a first port and a second port, the first port incommunication with the transmit switch and the second port incommunication with an antenna, the coupler configured to provide atransmit signal from the transmit switch to the antenna; and a powermeasurement module in communication with the coupler, the powermeasurement module part of a coupled path that is separate from theplurality of transmit paths.
 2. The antenna switch module of claim 1wherein the power measurement module does not contribute to an insertionloss within the plurality of transmit paths.
 3. The antenna switchmodule of claim 1 wherein the power measurement module includes a firstswitch and a second switch, the first switch configured to switchbetween connecting a third port of the coupler to a third switch and afourth port of the coupler to the third switch, and the second switchconfigured to switch between connecting the third port of the coupler toa termination resistor and the fourth port of the coupler to thetermination resistor.
 4. The antenna switch module of claim 3 whereinthe third port of the coupler is connected to the third switch when thefourth port of the coupler is connected to the termination resistor, andthe third port of the coupler is connected to the termination resistorwhen the fourth port of the coupler is connected to the third switch. 5.The antenna switch module of claim 3 wherein the power measurementmodule further includes the third switch and a diplexer in communicationwith the third switch, the third switch configured to switch betweenconnecting one of the third port of the coupler or the fourth port ofthe coupler to one of the diplexer or a common coupler output.
 6. Theantenna switch module of claim 5 wherein the common coupler outputcorresponds to a power measurement for a third RF band, the third RFband not used for carrier aggregation transmission.
 7. The antennaswitch module of claim 5 wherein the diplexer is configured to multiplexa first signal corresponding to the first RF band and a second signalcorresponding to the second RF band.
 8. The antenna switch module ofclaim 5 wherein the diplexer is configured to output a first powermeasurement corresponding to the first RF band and a second powermeasurement corresponding to the second RF band.
 9. The antenna switchmodule of claim 3 wherein the power measurement module further includesa low pass filter, a high pass filter, and the third switch, the thirdswitch being a single pole three throw switch, the first throwconfigured to connect the first switch to the low pass filter, thesecond throw configured to connect the first switch to the high passfilter, and the third throw configured to connect the first switch to acommon coupler output without a filter.
 10. The antenna switch module ofclaim 1 wherein the power measurement module includes the coupler.
 11. Atransceiver comprising: a power amplifier module including a pluralityof power amplifiers, each power amplifier from the plurality of poweramplifiers corresponding to a different radio frequency band; and anantenna switch module in communication with the power amplifier module,the antenna switch module including a band selection switch, a coupler,and a power measurement module, the band selection switch incommunication with a plurality of band paths, at least one of the bandpaths supporting carrier aggregation transmission of a first RF band anda second RF band, the coupler including a first port and a second port,the first port in communication with the band selection switch and thesecond port in communication with an antenna, the coupler configured toprovide a transmit signal from the band selection switch to the antenna,and the power measurement module in communication with the coupler, thepower measurement module part of a coupled path that is separate fromthe plurality of band paths.
 12. The transceiver of claim 11 wherein thepower measurement module includes a plurality of switches configured toregulate providing a power measurement from the coupler to at least oneof the plurality of power amplifiers.
 13. The transceiver of claim 12wherein the power measurement corresponds to one of an output power atthe antenna or a reflected power from the antenna.
 14. The transceiverof claim 11 wherein the power measurement module further includes afirst diplexer in communication with one of the plurality of switches,the first diplexer configured to multiplex a first signal correspondingto the first RF band and a second signal corresponding to the second RFband.
 15. The transceiver of claim 14 further comprising a seconddiplexer, the second diplexer in communication with a first poweramplifier and a second power amplifier from the plurality of poweramplifiers, the first power amplifier corresponding to the first RF bandand the second power amplifier corresponding to the second RF band. 16.The transceiver of claim 15 wherein the second diplexer is configured tomultiplex a third signal corresponding to the first RF band and a fourthsignal corresponding to the second RF band.
 17. The transceiver of claim16 wherein the first signal and the third signal are the same frequencyand the first signal has a different power level than the third signal,and the second signal and the fourth signal are the same frequency andthe second signal has a different power level than the fourth signal.18. The transceiver of claim 15 wherein the second diplexer generates a1-2 dB insertion loss and the first diplexer generates a 2-5 dBinsertion loss.
 19. The transceiver of claim 11 wherein the poweramplifier module is configured to modify the input power to at least onepower amplifier from the plurality of power amplifiers based at least inpart on a power measurement signal from the power measurement module.20. A wireless device comprising: an antenna configured to receive andtransmit a wireless signal, the antenna capable of transmitting acarrier aggregation signal; and a transceiver in communication with theantenna, the transceiver including a power amplifier module and anantenna switch module in communication with the antenna and the poweramplifier module, the antenna switch module including a band selectionswitch, a coupler, and a power measurement module, the band selectionswitch in communication with a plurality of band paths, at least one ofthe band paths supporting transmission of a carrier aggregation signalincluding at least a first signal of a first RF band and a second signalof a second RF band, the coupler configured to provide a transmit signalfrom the band selection switch to the antenna, and the power measurementmodule part of a coupled path that is separate from the plurality ofband paths.